public class Example4_10 {
    public static void main(String args[]) {  
      Lader.下底=100;
      Lader laderOne = new Lader();
      Lader laderTwo = new Lader();
      laderOne.设置上底(28);
      laderTwo.设置上底(66);
      System.out.println("laderone的上底:"+laderOne.获取上底());
      System.out.println("laderone的下底:"+laderOne.获取下底());
      System.out.println("ladertwo的上底:"+laderTwo.获取上底());
      System.out.println("ladertwo的下底:"+laderTwo.获取下底());
    } 
}
